Vermont AOT
Bridge Maintenance and Preservation Conference
July 1, 2008
George A. Christian, P.E.
Inspection Data for Bridge Asset
Management
New York State
Department of Transportation
Outline
Bridge Management Background
NYS Bridge Evaluations
Background
Bridge inspection Program Inspection Data
Bridge Evaluation Programs
Bridge Asset Management Strategies
Bridge Management analysis methods
Asset Management
“Transportation Asset Management is a
strategic
and
systematic
process of operating,
maintaining, upgrading and expanding physical
assets effectively throughout their lifecycle. It
focuses on business and engineering practices
for resource allocation and utilization, with the
objective of
better decision-making
based upon
quality information
and
well-defined objectives
.”
Bridge Management Background
To manage bridges effectively we need the
following primary components:
Inventory definition
Current condition assessment
Knowledge of bridge vulnerabilities.
Tracking of needs and projects
Economic evaluation of potential actions
Forecasting of deterioration and needs
Photo and document archive
NYS Bridge Management System
Inventory Data
Bridge Inspection
Condition Assessment
Vulnerabilities
Bridge Network Modeling
Resource Allocation
NY State
Bridges
Owners: NYSDOT, Local
Gov’ts, Authorities
17,400 bridges carry public
NYS Bridge Ownership
(Local) 8587 (Other) 1187 (State) 7632NYSDOT Bridge Evaluations
Program, in current format, developed in
early 1980’s
Bridge Inspection (general and diving) Detailed Bridge Inventory -- BDMS
Load Capacity Evaluation (Rating, Posting)
Bridge Safety Assurance (Vulnerabilities) Program
Bridge Inspection program is the primary data
source for all evaluation functions
NY’s bridge inspection program
Key Features
Clear mandate
Centralized Responsibility and
oversight
Funding / Resource Priority Quality Provisions
Critical Findings Procedure Safety Centric
Element Level
NYS Bridge Inspection Program
NYSDOT inspects State and Local owned
highway bridges in New York State
Inspection Team Leader must be a licensed
Professional Engineer (P.E.)
Biennial Inspection Program
Interim Inspections
Element Level Inspections
Examine and evaluate all elements of the
bridge (Visual, Tactile, Sounding)
Rate 47 elements
22 common to all bridges 25 on span by span basis
Document and photograph all “deficient” elements Measure and sketch deterioration and scour as
NYS Bridge Inspection Rating Scale
7 -- New condition, no deterioration
6
--5 -- Minor deterioration and
functioning as designed
4
--3 --Serious deterioration or
not functioning as designed
2
--1 -- Totally deteriorated or failed
condition
Defic ient N o n-D e ficientGood
Fair
Poor
NYS Condition Rating
It is a rating calculated based on weighted
inspection ratings of several components
Uses 13 different element ratings
When multiple rated elements exist, such as
abutment backwalls, the calculation utilizes lowest rated element
If C.R. < 5.00, the bridge is considered “Deficient”
according to NYSDOT
C.R. is NYSDOT’s most widely used bridge
Uses of Inspection Data
Providing Data for Program Planning
Used for developing capital program by using data with
BMS software
Used to compute “Sufficiency Rating” (measure of the
bridge’s ability to remain in service) to determine federal funding eligibility
Evaluation Functions
Inspection report used as a basis for structural integrity
evaluations, load rating, and other functions
Uses of Inspection Data
Scheduling Maintenance Activities
Emergency Repairs Flag Repairs
Corrective Maintenance Preventative Maintenance
Satisfying Federal and State Reporting
Requirements
Annual “Federal Tape”
Annual NYS “Report of Bridge Management and Inspection
Uses of Inspection Data
Forecasting
Element deterioration Condition rating trends Work strategy forecasts
Cost estimating
Load Rating /
Posting /
Permit Reviews
State and Federal Requirements
NYSDOT Load Rating system
Bridge structural element database Use AASHTOWare® VIRTIS
Bridge Safety Assurance Program (BSA)
“Vulnerability Assessments”
Program of assessment of bridges’ vulnerability to
structural failure due to their inherent characteristics or due to extreme events
Assessments are made for individual failure modes
“Identify causes of failure beyond condition”
(Why do Bridges Fail?)
NYSDOT Bridge Safety Assurance Program
Systematic evaluations of bridges based on failure
modes.
Hydraulics Steel Details
Overload Concrete Details Collision Earthquake
Evaluate statewide bridge population:
Screen ÆAssess ÆClassify
Vuln. Classifications consider failure likelihood and
consequence.
Evaluation data needs collected during bridge
NYSDOT Bridge Safety Assurance
Vulnerability Assessment Procedures
Assessment Manuals Refined flowchart
methods for screening
Follow up analysis for
higher vulnerabilities
Bridge Inventory database
for screening and assessment updates
NYSDOT Bridge Safety Assurance Program
Vulnerability Ratings
(for each Failure Mode)
1.
Safety Priority Action
2.Safety Program Action
3.Capital Program Action
4.
Inspection Program Action
5.No Action
BSA
Safety Priority Action
Scour Vulnerability
Mitigation
Scour Retrofits
Flood Warning Action
Plan
Post Flood
BSA Capital Program Action
NYSDOT
Bridge Management Strategy
Goal Oriented
Decentralized-but with central oversight
Combined Capital and Maintenance
programs
Least cost analysis for MR&R alternatives
Maintenance /Operations First
NYSDOT Bridge Goals
Eliminate Critical conditions:
Low critical element ratings High BSA vulnerabilities
Preservation:
Reduce the overall number of deficient bridges Maintain Interstate bridges in good condition Maintain NHS bridges in at least fair condition
Serviceability
Reduce load restrictions
Performance Measures
Percentage of deficient bridges
Statewide Interstates
NHS
Number of bridges with critical elements rated
less than 3 (serious deterioration)
Serviceability by Hwy. classification
Number of bridges with load restrictions
Maintenance / Operations First
NYSDOT Bridge Maintenance
Corrective
Maintenance
Preventive (Cyclical)
Maintenance
$100 Million program
(out of $600 M state bridge program) In-house and contractedBridge Maintenance
Corrective Maintenance
“Element Level” work
Element inspection
condition info.
ID work candidates Performance measure Federal-aid (HBP) eligible
Delivery Initiatives
Job-order contractsBridge Maintenance
Preventive (Cyclical) Maintenance
Washing (2 yr. cycle)
Lubricate Bearings (4 yr.) Deck Sealing (4 yr.)
Painting (12 yr.)
Deck Overlay (12 yr.)
Replace Deck Joints (as
needed)
r
NYSDOT Bridge Preservation Status
4.4 $250K $5K 4740 Fair Bridges 790 Poor Treatment Costs / Bridge Maintenance Candidates
Major Rehab or Replacement Candidates
2370 Good Bridges
5.8
$3.7M
Curve w/ Corrective Maintenance Curve w/out Corrective Maintenance
Local Projects
Included in Regional program updates
Fed. Aid “pass-thru” projects (local let)
DOT Oversight and Assistance
Local Projects Manual documents project
development process
Statewide Conference on Local Bridges
Information exchange Training
Bridge Management Analysis Tools
Deterioration modeling
Needs assessment models
Cost assessment
Forecasting
Deterioration Modeling
Cost Modeling
Bridge unit cost data
Replacement cost estimating model
Based on historical data
Base area costs Features costs
Continuously updated
Maintenance and Rehab costs:
Inspection condition data determines work
strategies—element combinations
Bridge Network Analysis
Bridge Program Worksheet
Identifies program candidates for goal
attainment using:
Condition (BDMS)
Inventory
Element and bridge inspection condition values
BSA vulnerabilities (BSA dB) Program Status (PSS)
Deterioration module
Evaluates program updates
Forecasts
Bridge Network Analysis
Bridge Needs Assessment Model (BNAM)
Forecasting-- Identifies present and future
improvement needs for highway bridges
Regional bridge program development and
evaluation
Statewide bridge needs analysis and resource
allocation
Uses Condition Rating as performance measure Scenario analysis—treatment strategies, funding
Bridge Network Analysis
Program Evaluation and Forecasts
State Highway Bridge Trend and Forecasts
26 27 28 29 30 31 32 33 34 35 36 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 Year P e rc en t D e fi ci en t b y N u m b er
Next Steps
Improve on element level data for BMS
purposes
condition state extents
Improve cost estimating modules
Optimization
Quantify life cycle costs
Preservation costs User costs
AASHTOWare® PONTIS
BMS Software
Licensed by most State DOT’s for over 15
years.
Comprehensive BMS features
Optimization
Pontis 5.2 (2009)
Software will feature a project focus with vastly
improved project analysis capabilities.
Multiple objective modeling framework. Incorporation of bridge risks.
Pontis implementation Issues
Element level data
Uses AASHTO Core Element (CoRE) data
Collect CoRE data?
Translate NYS to CoRE? Define new elements?
Program Optimization assumptions
Optimal means the least long term benefit / cost for each
element state
MR&R benefits can be measured in two ways: future
cost avoidance or change in element value (Bridge Health Index).
Least Cost Optimization Results
Health Health Index Index Time TimeNear Term Long Term
Low High
Optimal Preservation
Long Long Term Term Cost Cost Condition Condition Poor Good Lowow High Cost Minimization PointSummary:
Bridge Inspection data →Asset management
Bridge inspection Data
Element level conditions
Non-condition data (serviceability, vulnerabilities) Accessible
Quality
Data supports program goals/ measures
Maintenance, Rehab, Replacement programs Bridge safety
Questions?
NYSDOT Office of Structures (518) 457-6827
